Kecleon, The Color Change Pokémon. It changes it's colour quickly to blend with its surroundings, however it cannot change it's zigzag pattern. Its ability of changing colour allows it to sneak up on it's prey unnoticed. It then attacks with it's long tongue to trap its prey

Battle Moveset

A Good Moveset for Kecleon would have to be this:

Attacks:

Focus Punch
Substitute
Return
Shadow Ball

Items Attached:

Leftovers

Preferred Nature:

Adament

Strategy Using Kecleon

Kecleon has a wide movepool and good stats in Attack and special defense. However, its speed is poor which can cause this pokemon problems.
However, this moveset may work to Kecleons advantage. Use Substitute and then focus punch, and even if the Substitute still breaks, Focus punch will still hit.
Shadow ball and Return are to cover any weaknesses that Focus punch doesn't work against. You could try this moveset if you wish: Skill swap, Shadow ball, Return, Toxic. Use Skill swap, then shadow ball, and when it changes type, use shadow ball again and it will be super effective(but this is standard and most people will expect it)

EV Corner:

Max out the EVs in Attack & HP for Kecleon with any remaining in Special Defense

Strategy Against Kecleon

Since Kecleon changes type to the attack of your attack, what you should do is hit it for example with a Rock Attack and then a Water. Or a Grass followed by Fire. Or to do more damge, Fire followed by Ground or Rock

Contest Moveset

A good Contest Moveset for Kecleon would have to be this for the Beauty Contest best with Modest, Mild, Rash or Quiet Nature:

Attacks:

Blizzard
Ice Beam
Rain Dance
Surf

Items Attached:

Blue Scarf

Strategy Using Kecleon

If you do the attacks in this following order you should have very few problems; 1st - Rain dance, 2nd - Water pulse, 3rd - Ice beam, 4th - Blizzard, 5th - Ice beam

Locations in Games

Ruby/Sapphire

Route 118, 119, 120, 121, 123, Route 120 (Devon Scope)

Colosseum

Trade from R/S

Fire Red/Leaf Green

Trade from R/S

Animé Appearences

Kecleon has had several Animé Appearences, several of them are cameos however. First a couple were on a blimp trying to foil Team Rocket from stealing their owner's stuff. After that, Harrison used it in a battle against Ash. After that its owned by a trainer who uses it in contests